Avalanche Advisory for Saturday, May 9, 2015

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has Low avalanche danger. Natural and human-triggered avalanches are unlikely. Huntington Ravine is under a General Advisory. You will need to do your own snow stability assessments when traveling in avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

AVALANCHE PROBLEM: Continue to manage your sluff, especially if you are above terrain hazards like cliffs and crevasses or on seldom skied lines. Warm temperatures last night at Ravine elevations made the threat of the following hazards grow worse in most locations:

FALLING ICE: Falling ice remains a big potential problem. Massive blocks still cling to the center headwall cliffs as well as the Sluice, directly above Lunch Rocks. Reduce time spent in areas with ice above and you will reduce this threat. Don’t underestimate the speed and random trajectory of chunks of falling ice. Many people have been seriously injured or killed from falling ice in Tuckerman Ravine. There are no warning signs for falling ice. Only one big chunk might fall in a day but that could be the piece that hits you.

UNDERMINED SNOW: This hazard develops where the snowpack has a stream of meltwater running beneath. Typical areas include Hillman’s Highway, Right Gully, Lobster Claw, and the exit from the bowl. In general, areas where you might expect the largest volume of flowing water will create the most undermining with a thinning snow bridge above. The main waterfall hole left of the Lip has grown considerably with the increasing flow due to melting. Give a wide berth to this and other holes in the snowpack!

CREVASSES: The number of crevasses is greatest in the Lip and Sluice, but other locations may have cracks opening up as well. These can be covered by breakable snow bridges. Some of these are wide enough to fall into and they are probably much deeper than you think due to the turn downslope that they make at the bottom. The largest concentration of these slots in Lip and Sluice is best avoided, especially when traveling on foot.

The Little Headwall has fully collapsed and is unskiable. People are still trying to find their way toward the Lower Snowfields in hopes of keeping their boards on as long as possible. If you try this, you are in for a bushwhack on the south side of the stream crossing if you avoid falling in. We recommend walking down the trail to Hermit Lake from the floor of the Ravine. From there, the Sherburne Ski Trail is open for skiing to the uppermost crossover. From there, walk the Tuckerman Ravine Trail back down to Pinkham.

THE BOTTOM LINE: Temperatures at the 4,000’ level are around 60F at 6:30 this morning with high thin clouds. Expect easily carvable snow on every aspect with sloppier, knee twisting snow on less travelled areas. Lobster Claw and Right Gully are still skiable but watch and listen for undermining on your ascent. Generally speaking, the left side of Tuckerman’s has fewer and less severe hazards from icefall, undermining and crevasses. Among the left side options, Hillman’s Highway and Left Gully are also the longest runs and are probably your best bet for good riding as well as avoiding a grim outcome due to an encounter with one of the hazards listed above. Be prepared for possible thunderstorm activity this afternoon.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
  • Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
  • For more information contact the Forest Service Snow Rangers, the Mount Washington Volunteer Ski Patrol, or the AMC at the Pinkham Notch Visitor Center and Hermit Lake.
  • Posted 7:25 a.m., Saturday, May 9, 2015. A new advisory will be issued tomorrow.

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713

2015-05-09 print friendly